Updated map sensors

[dub-disaster]

Do updates map sensors still read lower boost levels ? I intend on upping the boost from my k03  abs whilst my ecu is out for me to fit the chip I was going to put the larger map sensor in it now will it read the lower pressure levels though ?

[hayesey]

they still read from absolute zero up to what ever max pressure, usually people use 250kpa ones which will read up to 1.5 bar relative pressure.  What you do lose is some of the resolution of the smaller sensor because the output is still between 0 and 5v.  But it's not a problem as long as you have a chip to suit.

[dub-disaster]

I've got a ppp chip for 15 psi ko3 think it's g40008 in the description it doesn't say uprated map sensor so I geuss I'll leave it alone till I get the boost turned up. Thanks though haysey

[Andy]

An uprated MAP sensor requires a chip to suit. The ECU reads in a voltage from 0-5V for the MAP sensor signal and a 200kPa standard MAP sensor will read around 5V at 1 bar of boost (2 bar or 200kPa absolute pressure). A 250kPa MAP sensor will read 5V at 1.5 bar of boost.

You can see if you programmed a chip to run 80% injector duty cycle at 1 bar of boost (5V) on a stock MAP sensor, you'd not see 80% injector duty cycle on a 250kPa sensor until you're also getting 5V - i.e. running 1.5 bar. Hence why you need a chip to suit.

As Hayesey said, you lose a bit of resolution in the map as your 16 map points have to stretch from 0-250kPa rather than 0-200kPa, but in practice you don't really notice it! I've got a 300kPa sensor on mine...

[dub-disaster]

Cheers for cleaning that up for me. I'll keep my stock sensor and change it when I wind boost up, just thought I was going to save a bit of time whilst I had the ecu out.